/Engine/Plugins/Online/OnlineServices/Source/OnlineServicesCommon/Public/Online/LobbiesCommonTypes.h
Apply updated lobby data and generate changes. The LeaveReason provides context for members who have left since the most recent snapshot. Changing a lobby generates events for the local client.
[TOnlineResult](API\Plugins\OnlineServicesInterface\Online\TOnlineResult)< [FLobbyClientDataPrepareServiceSnapshot](API\Plugins\OnlineServicesCommon\Online\FLobbyClientDataPrepareServiceSn-) > PrepareServiceSnapshot ( [FLobbyClientDataPrepareServiceSnapshot::Params](API\Plugins\OnlineServicesCommon\Online\FLobbyClientDataPrepareServiceSn-\Params) && Params ) const